The present invention relates to a method and a device for the graphic display of driver information in a motor vehicle, it being possible, using a Graphical User Interface (GUI), to represent on any background of a common driver information display driver information originating from different individual devices connected to each other by a bus.
Although it is applicable to any motor vehicle, the present invention, and the problem underlying it, is discussed with reference to the display device situated on board an automobile.
In this respect, it should be noted that in the following the concept xe2x80x9cdriver information displayxe2x80x9d should be understood in a general sense, as a display in an instrument cluster, as a display in the center console of a motor vehicle, as a display in the rear of the motor vehicle, e.g., in the head restraints of the driver and passengers seats, etc.
Earlier, various individual devices having their own graphical user interfaces were installed in automobiles for the display of driver information, such as radio, telephone, navigational aids, etc. In this context, it has been found that it is inconvenient to provide each individual device with a graphical user interface because the latter can be imaged only on a relatively small individual driver information display of the specific device, for example, a liquid crystal display.
As a consequence of this disadvantage, motor vehicle manufacturers today make use of so-called common driver information displays, which are accommodated centrally in the center console or in the instrument cluster of the motor vehicle and which centrally display driver information originating in different specific instruments. These common driver information displays can have a large format and therefore a better resolution than the individual displays of the individual devices. In addition, the common driver information displays afford the possibility of color reproduction and of reproducing more attractive or easier-to-read symbols. The display form and the design can also be programmed as desired. Furthermore, uniform hardware can be used for different models and variants.
In order to be successful with respect to a product of this type, high-quality graphics are required. This can be achieved by assembling the total graphic image from pre-processed partial graphics. A partial graphic can be a symbol, an alphanumeric sign, a graphic, or a photo-realistic image. However, if a partial graphic of this type is inserted into any background, the result is disturbing effects such as the appearance of stepped areas between the background and the partial graphic.
In one method for superimposing background and partial graphics according to the related art, the background and the partial graphics exist as bitmaps. In this context, the pixels of the partial graphic bitmap which do not belong to the partial graphic are interpreted as transparent, and pixels that are assigned to the partial graphic to be displayed have priority with respect to the pixels of the background of the graphical user interface of the common driver information display. However, the result of superimposition achieved in this manner no longer shows the antialiasing present in the partial graphic against the background.
The problem underlying the present invention therefore can generally be formulated as displaying any and all partial graphics on a display that has any of the possible backgrounds, without disturbing effects.
The compositing (inserting a partial graphic into a background) can be improved. For every pixel (=picture element composed of red, green, and blue components) of the graphic, there exists an additional xcex1-value, which controls the combination of the pixels of the partial graphic and of the common background. These xcex1-values constitute the so-called xcex1-channel, which satisfactorily realizes the transition from the partial graphic bitmap (source) to the background (destination).
In the above-mentioned version, it has proven to be disadvantageous that in embedded systems such as are used in the motor vehicle area, the participating hardware components do not satisfy the requirements for these composition or compositing methods because the computational demands are too great.
In contrast to the known solutions, the display method according to the present invention has the advantage that pre-processed partial graphics are stored in the individual devices in a motor vehicle and only a few calculating operations are executed for a high-quality compositing of the driver information display, or of the calculating and display units assigned to it.
The idea underlying the present invention rests in the fact that compute-intensive image processing operations, such as texture-mapping of 3-D models, antialiasing (smoothing out stepped areas between the background and an inserted graphic object), etc., are carried out in advance using image processing software. The result can be stored in a bitmap using the so-called xcex1-channel. This has the advantage that partial graphics are pre-processed and are stored in advance in the corresponding individual devices as bitmaps. Therefore, these partial graphics can be combined as desired and can be inserted in a common background, in which, using the xcex1-channel, a high-quality total graphic can be achieved without stepped-area effects.
Since intensive computing operations are carried out in advance, smaller components having reduced power requirements can be used in the automotive area, because only the most necessary image processing operations are immediately carried out by the components used in the automotive area.
Each individual device, such as radio, telephone, and navigational aid, in the cockpit of a motor vehicle having a common driver information display as part of the basic equipment of the motor vehicle, contains the partial graphics required by the display such as traffic program symbol, route symbol, telephone numbers-display, etc., corresponding to the functions belonging to them that are to be represented in the common driver information display.
Therefore, every manufacturer himself can determine the presentation on the graphical user interface of the individual device provided by him without suffering a loss of quality in the compositing. In addition, the user has the option of setting his total graphic against any of the possible backgrounds because the compositing can be carried out in any color combination while maintaining the antialiasing of the partial graphics.
According to one preferred refinement, a filtering is carried out of a supersampling of the partial graphic bitmap.
According to one preferred refinement, from the partial graphic bitmaps, graphic double images are produced, in which color picture elements of the supersampling of the specific partial graphic bitmap that are assigned to the backgrounds of the partial graphic are displayed as black picture elements, and color picture elements that are not assigned to the backgrounds are displayed as white picture elements.
According to one preferred refinement, by filtering the supersampling of the corresponding graphic double images, gray-key images are generated which are assigned in each case to the corresponding partial graphic bitmaps, each picture element of the gray-key images having a corresponding xcex1-value assigned to it for specifying the gray tone.
According to one preferred refinement, the graphic images having the corresponding associated xcex1-channels are stored in the specific device in a compressed format.